White spot on nipple and pain when feeding

[Cydonia]

Today when DS has been feeding from my right boob it's been painful, my nipple is sore and I get a pain down the side of my boob a bit like a strong let down kind of pain. Just had a look and there is a small white spot on the nipple, nipple itself is more red than the other one. I've had a quick google, but that's made me more confused, seems it could be a 'bleb' or blister, blocked duct, thrush or herpes. Worried now as I have had a cold sore, that I could have infected DS. He was still feeding from it ok and there is milk coming out.
Has anyone else had this or know which it is likely to be? Typical it happens now when I can't get to see a doctor, just wondering if there's over the counter treatment or anything I can do?

I had this last week and hv said it was likely to be a blocked duct and to hand express, massage during and in between feeds and feed more regularly from that side. Sure enough after 2 days it had gone. Do keep an eye for any red patches, hotness or other infections of infection as a blocked duct can lead to mastitis

Sounds like it could be thrush, surface thrush and also in the milk ducts, see your GP or out of hours as it is incredibly painful and needs treatment.

Yes just seen your thread Whatever, should have checked before posting! Thanks for the tips, will see how it is in the morning and ring GP if very sore. I guess I should check DS's mouth too as if it is thrush I will have caught it from him?